Lyot filter (original) (raw)
Der nach seinem Erfinder, dem französischen Astronomen Bernard Ferdinand Lyot, benannte Lyot-Filter ist ein optischer Filter, der Doppelbrechung nutzt, um einen schmalen Durchlassbereich der übertragenen Wellenlängen zu erzeugen. Der Anwendungsbereich des Lyot-Filters sind die Astronomie, die Laserphysik, um durchstimmbare Laser zu realisieren, sowie die optische Datenübertragung.
| Property | Value |
|---|---|
| dbo:abstract | Der nach seinem Erfinder, dem französischen Astronomen Bernard Ferdinand Lyot, benannte Lyot-Filter ist ein optischer Filter, der Doppelbrechung nutzt, um einen schmalen Durchlassbereich der übertragenen Wellenlängen zu erzeugen. Der Anwendungsbereich des Lyot-Filters sind die Astronomie, die Laserphysik, um durchstimmbare Laser zu realisieren, sowie die optische Datenübertragung. (de) A Lyot filter, named for its inventor Bernard Lyot, is a type of optical filter that uses birefringence to produce a narrow passband of transmitted wavelengths. Lyot filters are often used in astronomy, particularly for solar astronomy. A Lyot filter is made from one or more birefringent plates (usually quartz), with (in multi-plate filters) each plate being half the thickness of the previous one. Because the plates are birefringent, the ordinary and extraordinary polarization components of a light beam experience a different refractive index and thus have a different phase velocity. Therefore, the polarization state of light with an arbitrary wavelength will in general be modified after a passage through the filter plate, and this causes a loss of optical power in a subsequent polarizer. For certain wavelengths, however, the optical path length difference is an integer multiple of the wavelength, so that the losses are very small. By rotating the plates, one can shift the wavelengths of the transmission peaks. Each stage of a Lyot filter is 1/2 the size of the preceding stage. The largest stage sets the bandwidth and the smallest stage sets the Free Spectral Range. If you use two of the second largest crystals it will increase the contrast of the desired line. If you split the crystals in half and add a 1/2 waveplates in the middle you can increase the field of view of the filter. The separation and narrowness of the transmission peaks depends on the number, thicknesses, and orientation of the plates. If electrically tunable birefringent elements are inserted (liquid crystal or electrooptic), then we obtain an "Electrically Tunable Lyot Filter". Liquid crystal tunable filters allow analogue tuning of the transmitted wavelength by carefully adjusting the voltage over the liquid crystal cells. Often these filters are based on the original Lyot design, but many other designs exist in order to achieve either narrow or broad band transmission, polarization selectivity, etc. Single and multi-plate Lyot filters are often used inside the optical cavity of lasers to allow tuning of the laser. In this case, Brewster losses from the plate and other intracavity elements are usually sufficient to produce the polarizing effect and no additional polarizers are required. Although their mechanisms are different, modelocking lasers and Lyot-filter lasers both produce a comb of multiple wavelengths which can be placed on the ITU channel grid for Dense Wave Division Multiplexing (DWDM) or used to give each suburban home its own return-signal laser wavelength in a passive optical network (PON) used to provide FTTH (Fiber To The Home). (en) Il filtro di Lyot è un filtro ottico composto da una lamina di un cristallo birifrangente interposta tra una coppia di polarizzatori fra loro paralleli e a 45° rispetto agli assi ottici della lamina. Prende il nome dall'astronomo francese Bernard Lyot. L'onda ottica polarizzata dal primo polarizzatore incide sulla lamina e viene scomposta in due componenti secondo gli assi ottici della lamina. E s è lo spessore della lamina e n la rifrangenza del cristallo fra le due componenti vi è uno sfasamento I due fasci all'uscita vengono ricomposti nel polarizzatore d'uscita e interferendo realizzano una trasmissione Accoppiando in serie più dispositivi è possibile aumentare la selettività del filtro fino ad ottenere larghezze di banda di un ordine di grandezza più strette di un filtro interferenziale. (it) |
| dbo:wikiPageID | 2929032 (xsd:integer) |
| dbo:wikiPageLength | 3725 (xsd:nonNegativeInteger) |
| dbo:wikiPageRevisionID | 1081119306 (xsd:integer) |
| dbo:wikiPageWikiLink | dbr:Quartz dbr:Passband dbr:Bernard_Lyot dbr:Birefringence dbr:Phase_velocity dbr:Optical_path_length dbr:Passive_optical_network dbr:Wave_plate dbr:Liquid_crystal_tunable_filter dbr:Fiber_to_the_premises dbr:Brewster's_angle dbr:International_Telecommunication_Union dbr:Astronomy dbc:Optical_filters dbr:Laser dbr:Sun dbr:Optical_cavity dbr:Refractive_index dbr:Lyot_depolarizer dbr:Lyot_stop dbr:Wavelength dbr:Wavelength-division_multiplexing dbr:Polarizer dbr:Filter_(optics) dbr:Modelocking |
| dbp:wikiPageUsesTemplate | dbt:Optics-stub dbt:Refimprove dbt:Reflist |
| dcterms:subject | dbc:Optical_filters |
| gold:hypernym | dbr:Filter |
| rdf:type | dbo:Software yago:WikicatOpticalDevices yago:WikicatOpticalFilters yago:Artifact100021939 yago:Device103183080 yago:Filter103339643 yago:Instrumentality103575240 yago:Object100002684 yago:OpticalDevice103851341 yago:PhysicalEntity100001930 yago:Whole100003553 |
| rdfs:comment | Der nach seinem Erfinder, dem französischen Astronomen Bernard Ferdinand Lyot, benannte Lyot-Filter ist ein optischer Filter, der Doppelbrechung nutzt, um einen schmalen Durchlassbereich der übertragenen Wellenlängen zu erzeugen. Der Anwendungsbereich des Lyot-Filters sind die Astronomie, die Laserphysik, um durchstimmbare Laser zu realisieren, sowie die optische Datenübertragung. (de) A Lyot filter, named for its inventor Bernard Lyot, is a type of optical filter that uses birefringence to produce a narrow passband of transmitted wavelengths. Lyot filters are often used in astronomy, particularly for solar astronomy. (en) Il filtro di Lyot è un filtro ottico composto da una lamina di un cristallo birifrangente interposta tra una coppia di polarizzatori fra loro paralleli e a 45° rispetto agli assi ottici della lamina. Prende il nome dall'astronomo francese Bernard Lyot. L'onda ottica polarizzata dal primo polarizzatore incide sulla lamina e viene scomposta in due componenti secondo gli assi ottici della lamina. E s è lo spessore della lamina e n la rifrangenza del cristallo fra le due componenti vi è uno sfasamento (it) |
| rdfs:label | Lyot-Filter (de) Filtro di Lyot (it) Lyot filter (en) |
| owl:sameAs | freebase:Lyot filter yago-res:Lyot filter wikidata:Lyot filter dbpedia-de:Lyot filter dbpedia-it:Lyot filter dbpedia-sk:Lyot filter https://global.dbpedia.org/id/GBpF |
| prov:wasDerivedFrom | wikipedia-en:Lyot_filter?oldid=1081119306&ns=0 |
| foaf:isPrimaryTopicOf | wikipedia-en:Lyot_filter |
| is dbo:knownFor of | dbr:Bernard_Lyot |
| is dbo:wikiPageDisambiguates of | dbr:Lyot |
| is dbo:wikiPageRedirects of | dbr:Lyot-Öhman_filter dbr:Birefringent_filter |
| is dbo:wikiPageWikiLink of | dbr:Michelson_interferometer dbr:Bernard_Lyot dbr:Birefringence dbr:John_Wainwright_Evans dbr:Index_of_physics_articles_(L) dbr:Interferometry dbr:List_of_inventions_named_after_people dbr:List_of_laser_articles dbr:Timeline_of_telescopes,_observatories,_and_observing_technology dbr:Waveplate dbr:H-alpha dbr:Liquid_crystal_tunable_filter dbr:Optical_filter dbr:Atomic_line_filter dbr:Istanbul_University_Observatory dbr:Tunable_laser dbr:Lyot dbr:Lyot_stop dbr:Lyot-Öhman_filter dbr:Birefringent_filter |
| is dbp:knownFor of | dbr:Bernard_Lyot |
| is foaf:primaryTopic of | wikipedia-en:Lyot_filter |